KCNA said in a statement early Sunday local time that Kim had supervised a “strike drill” -- essentially, a test of combat readiness -- of defense units in direction of the Sea of Japan, also known as the East Sea.

North Korean leader Kim Jong Un has expressed increasing frustration since Trump refused his demands for sanctions relief and walked out of their second summit in Hanoi in February. (Bloomberg)

President Donald Trump brushed off news of a possible weapons test by North Korea — confirmed Sunday by state media in Pyongyang — and vowed that his long-sought denuclearization deal with leader Kim Jong Un “will happen.”

KCNA said in a statement early Sunday local time that Kim had supervised a “strike drill” — essentially, a test of combat readiness — of defense units in direction of the Sea of Japan, also known as the East Sea. The tests were done to assess the accuracy of “large-caliber long-range multiple rocket launchers and tactical guided weapons,” the state media agency said.

South Korean authorities on Saturday flagged numerous short-range projectiles fired off North Korea’s eastern coast. The move was seen as Kim’s most provocative signal of frustration over talks with Trump following the pair’s failed summit in Vietnam in February.

South Korea revised its account of the nature and scale of the weapons discharged from the eastern port of Wonsan just after 9 a.m. Saturday local time. After first calling them “missiles,” South Korea’s Joint Chiefs of Staff later changed its description to “projectiles.”

“They emphasized technological sophistication and framed the exercise in fairly defensive terms,” Ankit Panda, adjunct senior fellow at the Federation of American Scientists, said after KCNA’s report. The lack of overt threats to South Korea may have been an attempt to limit damage to the agreement reached between the two Koreas in September, he said. Trump has cited Kim’s self-imposed freeze on missile and nuclear weapons tests to support his decision to continue negotiations with the North Korean leader. The descriptions of Saturday’s incident suggested the U.S. is less likely to conclude it was a violation of Kim’s pledge to refrain from testing.

“We are aware of North Korea’s actions tonight. We will continue to monitor as necessary,” White House Press Secretary Sarah Sanders said. National Security Adviser John Bolton briefed the president about the launch, according to a senior administration official, who asked for anonymity to discuss the matter.

The weapons were fired from the Hodo Peninsula, which has been the site of past live-fire artillery exercises, and traveled 70 to 200 kilometers (45 to 125 miles), the joint chiefs said earlier Saturday.

Even as a readiness drill, it was Kim’s most significant provocation since he launched an intercontinental ballistic missile in November 2017, declared his nuclear weapons program “complete” and opened talks. South Korea President Moon Jae-in’s spokeswoman condemned the incident, saying in a statement that they went against the September agreement to halt “hostile activities.”

Kim has expressed increasing frustration since Trump refused his demands for sanctions relief and walked out of their second summit in Hanoi in February. After a year of talks, Kim has made only a pledge to “work toward complete denuclearization of the Korean Peninsula,” without defining the phrase.

The North Korean leader accused the U.S. of “bad faith” during a meeting with Russian President Vladimir Putin in Vladivostok last week. He had earlier told North Korea’s Supreme People’s Assembly that he would wait “with patience till the end of this year” for the U.S. to make a better offer.

Drills may also signal displeasure with South Korea’s participation in joint military drills with the U.S., despite Trump’s decision to scale down those exercises. North Korean state media has repeatedly complained about the drills in recent weeks and Kim pledged “corresponding acts” during his speech last month to the rubber-stamp parliament.

South Korean Foreign Minister Kang Kyung-wha discussed Saturday’s incident with U.S. Secretary of State Michael Pompeo by phone, the ministry said in a statement. Nuclear envoy Lee Do-hoon made a separate call to U.S. Special Representative Stephen Biegun, who is slated to visit Japan and South Korea next week.

“This is an expected move from North Korea — not too provoking, but urging the U.S. to take a slightly stronger stance than their initial one,” said Kim Hyun-wook, of the Korean National Diplomatic Academy. “This seems like a message for Stephen Biegun’s planned trip to the peninsula.”

Biegun, the U.S. Special Representative to North Korea, travels to Tokyo on May 7 and to Seoul on May 9 to meet with Japanese and South Korean officials on efforts to advance the final, fully verified denuclearization of North Korea.

Japan’s defense ministry said Saturday that the country hadn’t detected any missiles entering its exclusive economic zone and as such there was no immediate impact to its national security.

Although Saturday’s launch was the most significant since Kim’s detente with Trump, North Korea has announced more limited weapons tests in recent months. Kim personally oversaw the test-firing of a “new-type tactical guided weapon” last month, which South Korea later said appeared to be a system intended for ground combat and not a ballistic missile.